Help identifying shower valve

Hi all. My name's Chris. Thanks for all the useful info I've gotten while lurking in the forums.
I'm remodeling my bathroom but left the existing shower valve in place. The closest I can find appears to be similar to a Kohler 303-k, but mine looks slightly different. I'm hoping the Kohler Coralis will fit since that's the only decent looking trim I can find that looks like it might work. The last shot is what's left of the old diverter. I'd greatly appreciate any help.
(I should've looked for a brand/model number before I closed the wall, but didn't realize it would be an issue at the time).

You obviously didn't get this job inspected...a tearout and replacement of the shower normally requires a permit. This type of remodel almost always requires bringing the system up to current code which means an anti-scald valve. Sometimes you luck out, but finding trim for an old valve is often tough.

It's sort of like finding repair parts for a Yugo. If you do find them and install them, you still have a Yugo. The hard part of the job is already done. You have the wall open with access to the valve. Get a Delta valve and the trim of your choice and live happily for many years to come.

Thanks for your quick replies. I took pictures of all the plumbing and wiring for future reference before I closed up the walls, but they're closed now. I haven't grouted the tile yet though, so if it's going to be a nightmare finding trim, better to rip it out now I guess. I'd like to leave it if at all possible though. Jimbo, I threw out the handles during demo. Jad, I wasn't planning on doing a shower tearout, just new wall finishes/shower trim. That is all existing plumbing in the pics. Thanks again.

Thanks HJ. I'd like to use the Kohler Coralais trim (best of limited options), but it says for use with k-303-k valve only. If that's the case, are the stems for the Trend & 303-k valve interchangable? If so, I could probably swap-out the stems to accomodate the Coralais trim.?

So I got the Kohler Coralais trim but the handles do not engage the hot & cold stems. There is a gap of about 1/4" from the tip of the stem to the serrated inner portion of the handle (not sure what this part is called). I'm trying to find a way to extend that inner portion but have been unable to find that part. Does anyone know what that piece is called? Sound feasible? Thanks in advance.